add try catch over publish

mqttclient.js

@@ -59,7 +59,12 @@ MQTTClient.prototype.resetbroker = function(topic, payload) {
 
 MQTTClient.prototype.publish = function(topic, payload) {
 	if (this.client && this.client.connected) {
-        this.client.publish(topic, payload);
+        try {
+            this.client.publish(topic, payload);
+        }
+        catch(e) {
+            
+        }
 	}
 	else {
 	}